<template>
  <div class="sidebar">
    <el-menu class="sidebar-el-menu"
             :default-active="onRoutes"
             :collapse="collapse"
             background-color="#324157"
             text-color="#bfcbd9"
             active-text-color="#20a0ff"
             unique-opened
             router>
      <template v-for="item in items">
        <template v-if="item.subs">
          <el-submenu :index="item.index"
                      :key="item.index">
            <template slot="title">
              <i :class="item.icon"></i>
              <span slot="title">{{ item.title }}</span>
            </template>
            <template v-for="subItem in item.subs">
              <el-submenu v-if="subItem.subs"
                          :index="subItem.index"
                          :key="subItem.index">
                <template slot="title">{{ subItem.title }}</template>
                <el-menu-item v-for="(threeItem,i) in subItem.subs"
                              :key="i"
                              :index="threeItem.index">{{ threeItem.title }}</el-menu-item>
              </el-submenu>
              <el-menu-item v-else
                            :index="subItem.index"
                            :key="subItem.index">{{ subItem.title }}</el-menu-item>
            </template>
          </el-submenu>
        </template>
        <template v-else>
          <el-menu-item :index="item.index"
                        :key="item.index">
            <i :class="item.icon"></i>
            <span slot="title">{{ item.title }}</span>
          </el-menu-item>
        </template>
      </template>
    </el-menu>
  </div>
</template>

<script>
import bus from "../common/bus";
export default {
  data () {
    return {
      collapse: false,
      items: [
        {
          icon: "el-icon-setting",
          index: "HomePage",
          title: "系统首页"
        },
        {
          icon: "el-icon-date",
          index: "DatabaseManage",
          title: "资料库管理",
          subs: [
            {
              index: "CertainBase",
              title: "特定页面库"
            },
            {
              index: "ArticleDatabase",
              title: "文章库"
            },
            {
              index: "FileManage",
              title: "文件库"
            },
            {
              index: "PhotoDatabase",
              title: "图片库"
            },
            {
              index: "ViedoDatabase",
              title: "视频库"
            }
          ]
        },
        {
          icon: "el-icon-tickets",
          index: "PublishArticle",
          title: "发布文章"
        },
        {
          icon: "el-icon-rank",
          index: "AdministratorManage",
          title: "管理员管理",
          subs: [
            {
              index: "AdministratorInfo",
              title: "管理员信息"
            },
            {
              index: "SuperAdministratorInfo",
              title: "超管信息"
            }
          ]
        },
        {
          icon: "el-icon-star-on",
          index: "ColumnManage",
          title: "栏目管理"
        },
        {
          icon: "el-icon-warning",
          index: "SystemManage",
          title: "系统管理",
          subs: [
            {
              index: "WebsiteInfo",
              title: "网站信息"
            },
            {
              index: "NavigationConfig",
              title: "导航配置"
            },
            {
              index: "SwipperConfig",
              title: "轮播配置"
            },
            {
              index: "FooterConfig",
              title: "底部信息配置"
            }
          ]
        }

      ]
    };
  },
  computed: {
    onRoutes () {
      return this.$route.path.replace("/", "");
    }
  },
  created () {
    // 通过 Event Bus 进行组件间通信，来折叠侧边栏
    bus.$on("collapse", msg => {
      this.collapse = msg;
    });
  }
};
</script>

<style scoped>
.sidebar {
  display: block;
  position: absolute;
  left: 0;
  top: 60px;
  bottom: 0;
  overflow-y: scroll;
}
.sidebar::-webkit-scrollbar {
  width: 0;
}
.sidebar-el-menu:not(.el-menu--collapse) {
  width: 220px;
}
.sidebar > ul {
  height: 100%;
}
</style>
